The literary documents considered in the previous chapter reveal the slow process of evolution leading up to a better understanding of the subject of volatile oils. In like manner, a short historical retrospect of the methods of distillation and distilling apparatus may result in an insight into the gradual development of the art of distillation and of the methods of preparation of distilled oils. The history of the evolution from the primitive Cucur-bita, the Alembic and the Berchile to the steam and vacuum apparatus of our own time reveals a long and varied course which had to be traversed by this apparently modern branch of industry in order to bring it to its present technical and scientific perfection.

As is well known, primitive man regarded fire as something supernatural. Thus the Greeks believed it to the gift of Prometheus and used it accordingly in their religious rites. The oldest tribes of the Persians worshiped it as a divine element. A more practical use was made of it by the Chinese, who in the remotest antiquity utilized it in the development of a most remarkable, though primitive industry. The oldest books of the Bible report that Tubal-Kain was "an instructor of every artificer in brass and iron";1) they also state that bricks were burnt2) for the construction of the tower of Babel. According to the apocryphal document, the Ayur-VedasJ) the Indians at an early date not only used furnaces for melting and firing, but also for distillation. They were used extensively by the Egyptians during their long and highly developed period of civilization.

1) Genesis, 4 : 22.

2) Genesis, 11:3.

3) See p. 16.

For more than ten centuries, from the time of the Arabians to the end of the middle ages, the solution of minerals, of vegetable and animal drugs with the aid of furnaces was regarded as a noble and "subtle" activity in the search for the philosopher's stone. This philosopher's stone was not only to serve the purpose of converting baser metals into gold, but also of preparing a quinta essentia for the maintenance and reestablish-ment of health and the prolongation of life. Hence the furnaces, apparatus, and implements constructed for the practice of the hermetic art and for alchemistic purposes are important, not only for their own sake, but as essential aids to technology. They afford an interesting illustration of the desire to solve the problems of a better knowledge of natural objects in so far as it can be gained by the direct or indirect action of heat as generated in the several types of furnaces used since antiquity. Thus the furnaces constructed for melting and sublimation were used in the search for the lapis philosophorum, the latter together with the furnaces used for distillation in the search for the quinta essentia of organic nature. As a final hypothesis, the doctrine of phlogiston was developed in the long epoch of practical endeavor and theoretic speculation. With its overthrow there were also abandoned at the close of the 18. century the beliefs in the miraculous, and the prevailing doctrines of the elementary nature of natural objects.

The first definite statement found in ancient writings which indicates a kind of primitive distillation, although probably not illustrated until the middle ages, is the mention of the method for obtaining oil of cedar, juaoelaLov (turpentine oil?), which occurs in the writings of Herodotus, Dioscorides and Pliny.1) This oil is said to have been obtained from the oleoresin by boiling with water in an open earthen kettle. The oil either collected at the surface of the liquid and was removed, or its vapors were condensed in layers of wool spread over sticks of wood laid cross-wise on the kettle as illustrated in figure 4. The wool when saturated was replaced from time to time by fresh portions and the oil expressed with the hands.

1) Herodoti Histories. Lib. II, 85. - Dioscorides, De materia medica. Lib. I, 34, 39, 80. - Plinii Historia naturalis. Lib. XV, cap. 6-7; and Lib. XVI, cap. 22. E pice fit, quod pissinum appellant, quum coquitur, velleribus supra habitum ejus expansis, atque ita expressis .... color oleo fulvus.

Authentic representations of the distilling vessels used by the Egyptians do not exist.1) Some of their forms of apparatus were undoubtedly adopted by the Arabians and improved by them. To the oldest known writings which give information on methods of distillation and distilling apparatus belong those of the Greek physician Dioscorides2) who lived during the first century of our era in Anazarbus, Sicily, and those of the Greek philosopher Zosimos3) of Panopolis. In a Arabian manuscript translation of Dioscorides' Liber de materia medica in the library at Leyden, distilling furnaces and apparatus are mentioned and described. These descriptions probably occur in the original Greek text. Among them are found the cucurbita and the alembic.4)

Just as pictures of animals have served as symbols in the oldest mythology of and as characters in writing by the earliest peoples, the forms of animals were used by the ancients as prototypes in the making of jewelry, and of all kinds of useful articles and apparatus. The same practice appears to have obtained in the making of primitive digestion and distilling vessels. Such pictorial representations have been carried over from the writings of Zosimos, and probably of others into the writings of the Arabians and from these into other alchemical works of the middle ages.1)

1) Egyptian and Greek distilling apparatus of the 3. and 4. centuries, which served primarily for the distillation of mercury, have been reproduced in Dujardin's L'artde la Distillation. Paris 1900. These illustrations were found in a manuscript of the end of the 10. century in the Marcus library in Venice and are copied from Berthelot's Introduct. a I'Etude de la Chimie des Anciens etdu Moyen-age. 1889.

2) See p. 19.

3)IV History Of The Methods Of Distillation And Of D 37 (of apparatus and furnaces). See p. 22.

4) Extracts from this as well as from the later Arabic texts of Rhases, also an unimportant illustration of an Arabic distilling apparatus, have been published by Prof. E. Wiedemann in vol.32 (1878), p. 575 of the Zeitschrift der deutschen morgenlandischen Gesellschaft.

Fig. 4.

Fig. 4.